Method For Cleaning The Interior Of An Above Ground Storage Tank

ABSTRACT

An apparatus and method for cleaning the interior of an above ground storage tank includes a nozzle assembly mounted to a cover on the storage tank sidewall having a horizontally extending wash pipe fixedly and a suction pipe for recirculation of spent fluids. The wash pipe has an interior segment which can be extended to a tank floor and is configured with a bend to extend along the tank sidewall to which is attached a submersible swivel joint fitted with a choked nozzle. The nozzle assembly is attached to a control assembly so that the direction of flow from the nozzle may be manipulated by rotation of the swivel joint from the exterior of the storage tank. The nozzle also may be adjusted so the direction of flow may follow the angle of the tank floor.

PRIORITY

This is a divisional application under 37 CFR 1.53 (b) entitled “Methodand Apparatus for Cleaning the Interior of an above Ground StorageTank”, The pending prior application is Ser. No. 13/456,746 filed onApr. 26, 2012 by applicant for “Method and Apparatus for Cleaning theInterior of an above Ground Storage Tank”, the entire contents of whichare hereby incorporated by reference. This application claims priorityto prior application Ser. No. 13/456,746.

FIELD OF INVENTION

This invention relates to the tank storage of crude oil and othervolatile liquids. More particularly, the application relates to anapparatus for cleaning the interior of an above ground storage tank. Theapparatus includes an articulating nozzle assembly that may bepermanently attached to the sidewall of the storage tank.

BACKGROUND OF THE INVENTION

Crude oil refineries typically employ a bank or battery of above groundstorage tanks that are used to hold liquids such as crude oil, heavyfuel oil, oil byproducts and the like. Contaminants, solid components,and heavier liquids that are suspended m the stored liquids willtypically settle after time to the bottom of a storage tank. Thesecontaminants, solid components, and heavier liquids will create sludge.This sludge can build up over time in an amount sufficient so as toreduce the tank capacity. The sludge buildup may also increase the riskof fire and explosion of retained liquids in the storage tank.Consequently, the sludge that is built up in the tanks comprising thestorage tank battery must be periodically removed from the tank.

A number of mechanical devices are utilized for cleaning tanks withoutthe necessity of having a worker enter the tank. Such devices employnozzles that are positioned at the top or the sides of the tanks to becleaned. These devices typically employ gimbal mounted nozzles withcomplicated nozzle guidance mechanisms. When positioned from the top,such devices cause high velocity fluid to be projected down against thetank floor which can cause wear on the tank integrity. When positionedfrom the sides, such devices fail to sufficiently clean the tank floorwhich typically has a slight downward slope towards its center. Further,while in use, typical devices have no way of removing spent fluid or theadherent sludge which has been removed. A need exists for a simple, usercontrolled cleaning device that may be deployed within the interior ofan above ground storage tank.

Further, fixed nozzle tank cleaning devices may cause canyons to beformed in the adherent sludge on the tank floor wherein the fluiddischarged from the nozzle will no longer remove the adherent sludge. Aswell, nozzles designed to be rotated within the tank can become lockedup by sludge which has been disengaged from the tank floor wherein thenozzle will no ionizer be allowed to rotate.

SUMMARY OF THE INVENTION

The present invention provides a simple, user controlled apparatus andmethod for deploying a cleaning nozzle within the it of an above groundstorage tank. The apparatus and method described includes anarticulating nozzle assembly. The nozzle assembly may be adapted forpermanent attachment in a manway cover attached in the verticallyextending sidewall of the storage tank or for attachment into a separatehatch or port positioned in the vertically extending sidewall of thestorage tank.

The articulating nozzle assembly may be comprised of a horizontallyextending wash pipe and a horizontally extending suction pipe fixedlymounted to the vertically extending exterior sidewall of a storage tank.The wash pipe extends through the tank sidewall so that the wash pipehas an exterior portion extending from the storage tank sidewall on theoutside of the storage tank and an interior portion extending from thestorage tank sidewall on the inside of the storage tank. The exteriorportion of the wash pipe has an exterior end configured for attachmentto and fluid communication with a high pressure fluid source. Theinterior portion of the wash pipe is configured to have a desired bendso that wash pipe will generally extend along the vertically extendingtank sidewall. The interior pipe may be vertically adjusted downward sothat it will sweep just above the tank floor.

The suction pipe extends through the tank sidewall so that the suctionpipe has an exterior portion extending from the storage tank sidewall onthe outside of the storage tank and an interior portion extending fromthe storage tank sidewall on the inside of the storage tank. Theexterior portion of the suction pipe has an exterior end configured forattachment to and fluid communication with a high pressure vacuumsource. The interior portion of the suction pipe may also be configuredto have a desired bend so that suction pipe extends along the verticallyextending tank sidewall. The interior portion of the suction pipe may bevertically adjusted downward so that it will sweep just above the tankfloor.

The suction pipe may be used to apply a vacuum suction to clear aroundthe tank sidewall, add cutter stock, or suction recirculating productfrom the tank to the fluid source and back through the nozzle. Bysuctioning the adherent sludge from around the nozzle assembly, theproblem of articulating nozzles becoming locked in place by disengagedsludge is resolved.

A submersible swivel joint, such as a Chiksan® swivel joint manufacturedby FMC Technologies, Inc., is attached at the end of the interiorportion of the wash pipe and the suction pipe to provide a fluiddischarge end to the wash pipe that extends generally perpendicular tothe vertically extending tank sidewall. The wash pipe discharge end ofthe wash pipe is fitted with a choked nozzle. In this configuration, thechoked nozzle will rotate about the centerline of the wash pipe by meansof the swivel joint. Similarly, the suction pipe suction end may befitted with a suction nozzle or funnel to direct the material beingvacuumed into the suction pipe.

The wash pipe and the suction pipe of the nozzle assembly may each befurther provided with a control assembly so that the rotation of thechoked nozzle about the centerline of the wash pipe and the suctionfunnel of the suction pipe can be manipulated from the exterior of thestorage tank. The choked nozzle may also be offset at a small angle tofollow the contour slope of the tank floor. The control assembly isgenerally comprised of a control hushing mounted in the sidewall of thestorage tank at a position adjacent to the exterior portion of the washpipe.

The control bushing is tined with a rotatable control shaft that has anexterior end extending generally perpendicular from the verticallyextending sidewall of the storage tank and an interior end that extendsinto the interior of the storage tank. The interior end of the controlshaft is fitted with a perpendicularly extending rod or bar fitted to asteering linkage. Exterior end of the control shaft is fitted with acrank or steeling wheel to facilitate rotation of the rotatable controlshaft.

The control shaft with its associated steering linkage is utilized torotatably control the position of the choked nozzle and suction funnelwith respect to the swivel joint. The associated steering linkage can beany suitable linkage such as linkage associated with an eccentric geardrive, rack and pinion, cam, or wheel mechanisms.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cutaway perspective view of a storage tank fitted with thearticulating nozzle assembly described herein.

FIG. 2 is an outside elevation view of the above ground storage tankcleaning assembly shown in FIG. 1.

FIG. 3 is an interior elevation view of the above ground storage tankcleaning assembly shown in

FIG. 4 is a side partial cross-section view of the above ground storagetank cleaning assembly shown in FIG. 1.

FIG. 5 is a top partial cross-section view of the above ground storagetank cleaning assembly shown in FIG. 1.

FIGS. 6A and 6B are a side partial cross-section view of the verticalarticulation of the nozzle assembly shown in FIG. 1.

FIG. 7 is a schematic diagram of the vacuum system assembly of the aboveground storage tank cleaning assembly shown in FIG. 1.

FIG. 8 is a schematic view of the vacuum assembly above ground storagetank cleaning assembly.

FIG. 9 is an isometric view of the suction section of the above groundstorage tank cleaning assembly being articulable above the tank floor ofan above ground storage tank.

DESCRIPTION OF EMBODIMENT

FIG. 1 shows a cutaway perspective view of an above ground storage tank(40) having a vertically extending sidewall (42) that separates the tankexterior (43) from the tank interior (45). The sidewall (42) of thestorage tank (40) is fined with one embodiment of an articulating nozzleassembly (10) comprised of a nozzle section (12), a suction section(13), and a nozzle steering or control section (14). The nozzle assembly(10) is used for cleaning the interior of the storage tank (40). Thenozzle assembly (10) may be permanently or removably fitted on thestorage tank (40) by attachment to a manway cover, hatch, or port (3) ofan opening (32) in the sidewall (42) of the storage tank (40). Thenozzle assembly (10) may also be permanently or removably fitted on thestorage tank (40) by attaching it to a separate hatch, port cover, orother opening positioned in the vertically extending sidewall (42).

The nozzle section (12) of the assembly (10) is fitted to a highpressure fluid supply line (50) that is attached to a fluid supply, suchas a water or crude oil supply, and pump system (52) so that wash fluidmay be injected into the storage tank (40). The suction section (13) isattached to a vacuum system (54) which recirculates suctioned fluids tofluid supply and pump system (52).

As shown in FIG. 2 and FIG. 3 the nozzle assembly (10) is fitted to thetank sidewall (42) where nozzle section (12) will be positioned adjacenttank floor (45A). However, the storage tank (40) may also be providedwith a separate hatch, opening, or port, not shown, positioned in adesired location in the side wall (42) where the apparatus (10) mightalso he attached.

FIG. 4 shows a side partial cross-section view of the storage tank (40)with the tank sidewall fitted with the articulating nozzle assembly(10). In the interest of clarity, suction section (13) is shown at aposition above nozzle assembly (12) though suction section (13) will bepreferably positioned on the tank sidewall at a position in line with orbelow nozzle assembly (12) as needed in order to achieve adequatesuction of fluids.

The nozzle section (12) of the nozzle assembly (10) is comprised of ahorizontally extending wash pipe (34) that is fixedly mounted to thevertically extending sidewall (42) of the storage tank (40). The washpipe (34) extends through the tank sidewall (42) so that the wash pipe(34) protrudes into the interior (45) of the storage tank (40) in adirection generally perpendicular to the tank sidewall (42) and has anexterior portion (34A) that extends away from the storage tank sidewall(42) on the tank exterior (43) of the storage tank (40) and an interiorportion (34B) that extends from the storage tank sidewall (42) into thetank interior (45) of the storage tank (40).

The exterior portion (34A) of the wash pipe 04) has an exterior end (3d) configured for attachment to and fluid communication with the highpressure fluid line (50) at the tank exterior (43) by means of anattachment flange (38) or other attachment means. The interior portion(34B) of the wash pipe (34) has an interior end (35) configured forattachment to and fluid communication with a pipe segment (31) in orderto extend the interior portion (34B) of the wash pipe (34) along thevertically extending tank sidewall (42) in the tank interior (45).

Pipe segment (31) has a discharge end (35A) that is configured forattachment to the swivel end segment (33A) of a submersible joint (33),such as a Chiksan® swivel joint manufactured by FMC Technologies, Inc.The swivel joint (33) has a discharge end (37) that is fitted with achoked nozzle (39). In this configuration, the choked nozzle (39) willbe rotatably positionable within the interior (45) of the tank (40) bymeans of the swivel joint (33). The wash pipe (34) can be adjusted,preferably by lengthening pipe segment (31), to allow the choked nozzle(39) of the nozzle section (12) to be extended adjacent to, and in usesweep slightly above, the tank floor (45A).

Highlighted area 6 shown in FIG. 4 refers to articulating nozzle (39)which is shown in FIGS. 6A and 6B. FIG. 6A shows nozzle (39) in ahorizontal position and FIG. 6B depicts an alternate position of thearticulating nozzle (39) offset at a desired downward angle (α) tofollow the downward sloped surface of the tank floor (45A). Offsettingnozzle (39) at downward angle (α) allows improved mixing at the floor,without creating potential for damaging the floor by directing fluidforces at a relatively perpendicular angle to the tank floor (45A) or atan angle here the fluid forces generated by the nozzle (39) will causewear or damage to the floor surface. The angular adjustment of nozzle(39) in combination with the adjustment of interior end (35) to positionthe nozzle section (12) to sweep slightly above the tank floor (45A)will provide a means to clear adherent sludge, oil, or other petroleumslurry from the surface of the tank floor (45A) while improving themixing at the tank floor (45A) without creating a potential for damagingthe floor by projecting high velocity fluids against the tank surface.

The high velocity fluids projected by the nozzle section (12) may be anywater, crude oil, or other fluid substance which may be directed in ajet or plume to dissolve and suspend accumulated sludge from a tankfloor (45A).

The suction section (13) of the nozzle assembly (10) is comprised of ahorizontally extending draw pipe (44) that is fixedly mounted to thevertically extending sidewall (42) of the storage tank (40). The drawpipe (44) extends through the tank sidewall (42) so that the draw pipe(44) protrudes into the interior (45) of the storage tank (40) in adirection generally perpendicular to the tank sidewall (42). Theexterior portion (44A) of the draw pipe (44) extends away from thestorage tank sidewall (42) on the tank exterior (43) of the storage tank(40) and the interior portion (44B) of the draw pipe (44) extends fromthe storage tank sidewall (42) into the tank interior (45) of thestorage tank (40).

The suction section (13) is attached to a collection hose or pipe, shownas disposed vacuum line (26), having a vacuum connection (26 a) forconnecting the vacuum line (26) to the vacuum system (54) for producinga vacuum force (Δ) at the suction section (13) to suction the adherentsludge (81) freed by nozzle section (12).

The exterior portion (44A) of the draw pipe (44) has an exterior end(47) configured for attachment to the vacuum line (26) at the tankexterior (43) by means of an attachment flange (38) or other attachmentmeans. The interior portion (44B) of the draw pipe (44) has an intakeend (49) that is fitted with a vacuum nozzle or funnel (46). In thisconfiguration, the funnel (46) will be capable of clearing obstructionsfrom around opening (32), can add cutter stock to the amalgam within thestorage tank (40), or can be used to suction recirculating product fromthe tank (40) to water supply and pump system (52) in order toredistribute the recirculating product back through the nozzle (39) intothe interior of the tank (40). Cutter stock may be any chemical orsubstance for aid in dissolving and breaking up of adherent fluid fromthe tank floor (45A).

FIG. 3, FIG. 4, and FIG. 5 show the control section (14) of the nozzleassembly (10). Control section (14) is fitted to the nozzle section (12)so that the position of the choked nozzle (39) by means of the swivelsection (34A) of the submersible joint (33) can be manipulated by a userfrom the exterior of the storage tank (42). The control assembly (14) isgenerally comprised of a rotatable control shaft (24) that has anexterior end (23) extending generally perpendicular from the verticallyextending side spall (42) of the storage tank (40) and an interior end(25) that extends into the interior (45) of the storage tank (40). Thecontrol shaft (24) is fitted through a control bushing, (22) mounted onthe tank sidewall (42.) of the storage tank (40) at a position adjacentto the exterior portion (34A) of the wash pipe (34).

The interior portion (25) of the control shaft (24) has aperpendicularly extending control rod (27) pivotally fitted to asteering linkage (28) that is pivotally attached to the swivel joint(33). The exterior end (23) of the control shaft (24) is fitted with asteering wheel (29) to facilitate rotation of the rotatable controlshall (24). A handle projecting, from the control shaft such as a crank,lever or other device for turning the control shaft (24) may be utilizedas a replacement for the steering wheel (29). When interior end (35) isadjusted to place nozzle section (12) adjacent the tank floor (45A),interior portion (25) of the control shaft (24) will be proportionatelyadjusted in order to articulate swivel joint (33).

As shown in FIG. 5, a top partial cross-section of a storage tank fittedwith the articulating nozzle assembly (10), rotation of the controlshaft. (24) of the nozzle assembly (12) will move the control rod (27)and by the associated steering linkage (28) control position of thechoked nozzle (39) and thereby the direction of flow from the chokednozzle (39) as the swivel joint (33) pivots about the swivel segment(33A).

The control assembly (14) and associated steering linkage (28) can beany suitable steering mechanism such as an eccentric gear drive, rackand, pinion, cam, or Wheel mechanisms. An automated device or a poweredturning mechanism may also be incorporated into the control assembly(14). For example, the control assembly (14) may be fitted with a motor,such as an electric or hydraulic motor, to rotate the control shaft (24)or to otherwise manipulate the steering linkage (28) as a substitute forthe manual steering wheel (39).

As shown in FIG. 7 and 8, the Vacuum system (54) is comprised of a motor(58) and vacuum pump (55) connected to a vacuum tank (56) by anassociated vacuum line (60 c). The vacuum tank (56) is connected atentry (70 c) to a vacuum line (60 b) that is connected at entry (70 b)to a fluids collection chamber (62). The fluids collection chamber (62)is further connected at entry (70 a) to a fluids vacuum line (60 a). Thefluids vacuum line (60 a) is connected to the vacuum connection (58) ofvacuum line (26) shown in FIG. 1. When activated the vacuum pump (55)will create a vacuum within vacuum tank (56) via vacuum line (60 c), aVacuum. within the fluids collection chamber (62) via vacuum fine (60b), and provide a desired suction force (Δ) at the funnel (46) via fluidvacuum line (60 a) which is in communication with vacuum line (26) bymeans of vacuum connection (26 a). The suction force (Δ) at the funnel(46) will draw the freed adherent sludge (81) from the tank (40) intothe fluids collection chamber (62).

The adherent sludge (81), drawn by suction through funnel (46) andvacuum line (26) into vacuum line (60 a), is delivered through entry (70a) into the fluids collection chamber (62). The collected sludge (81),and any extraneous fluids drawn along with the sludge (81), will thenspill into the fluids collection chamber (62) where it will becollected. The fluids collection chamber (62) is provided with anairtight fluids exit port (64 a) having an associated fluids dump valve(61). The fluids exit port (64 a) is in communication with a fluidsdischarge line (64 b). A discharge outlet (65) from the discharge line(64 b) delivers fluids discharged from the fluids collection chamber(62) into a fluid holding tank (66) or to another desired location forultimate disposal. A dump pump (68) may be provided with the dischargeline (64 b) to facilitate removal of the sludge (81) and any extraneousfluids from the fluids collection tank (62). The fluids dump valve (61)may be an automatic or manually operated valve such as a butterflyvalve, a gate valve, or a ball valve.

The vacuum tank (56) may be provided with a vacuum control port (57) incommunication with a vacuum control or relief valve (59). The vacuumrelief valve (59) is used to regulate the suction created in the vacuumtank (56) and thus the suction created in the vacuum line (26) andultimately the suction force (Δ) created at the funnel (46).

Pressure monitors (72) may be positioned at desired locations throughoutthe vacuum system (54) such as in the vacuum tank (56), the fluidscollection chamber (62), or the vacuum line (26) to monitor and generatepressure signals (71). These pressure signals (71) may be delivered to acontrol panel (70) from which control signals (73 a) may be generatedand transmitted to the vacuum control valve (59), pump (55), or motor(58) as necessary to regulate the vacuum created in the vacuum tank (56)and the quantity of fluids delivered to the fluids collection chamber(62) and to otherwise control the vacuum system (54). The control panel(70) may also be used to receive, generate, and transmit control signals(73 b) to and from the fluids dump valve (61) at the fluids exit port(64 a) of the fluids collection chamber (62) and to the dump pump (68)to regulate removal of the collected fluids from the fluids collectionchamber (62).

A suction force (Δ) is then created at the tunnel (46) by the vacuumsystem (54) and directed by the funnel (46) to suction the floatingsludge (81), thereby clearing the area about the tank sidewall (42) oftank (40), drawing the floating sludge (81) into the fluids collectionchamber (62) of the vacuum system (54).

The vacuum system (54) is assembled with motor (55) connected to thevacuum pump (58), vacuum pump (58) connected to vacuum tank (56) viavacuum line (60 c), fluids collection tank (62) connected to vacuum tank(56) via vacuum line (60 b), and vacuum line (26) connected to fluidscollection tank (62) via fluids Vacuum line (60 a).

With the vacuum system (54) attached to the vacuum line (26) 01 thesuction section (13), the motor (55) and vacuum pump (58) is thenactivated to create a vacuum in vacuum tank (56). Creating a vacuum inthe vacuum tank (56) will create a vacuum in the fluids collection tank(62), a suction force (Δ) in fluid vacuum line (60 a) and in vacuum line(26), and a suction force (Δ) at the funnel (46) whereby the sludge (81)will be drawn through funnel (46), vacuum line (26), and fluid vacuumline (60 a) into fluids collection chamber (62) where the suctionedsludge (81) will be collected.

Controlling the suction force (Δ) and the flow of sludge (81) into andout of the fluids collection chamber (62) may be accomplished bymanually controlling the vacuum relief valve, the dump valve (61), thedump pump (68), the motor (55), and the vacuum pump (58). Controllingthe suction force (Δ) and the flow of sludge (81) into and out of thefluids collection chamber (62) may also be accomplished by automaticallycontrolling the vacuum relief valve, the dump valve (61), the dump pump(68), the motor (55), and the vacuum pump (58) by providing a generatingcontrol signals (71 and 73 a, 73 b) to and from the control panel (70)and the associated valves, pumps, and motors.

Further, the funnel (46) will be capable of adding cutter stock to theamalgam within the storage tank (40) by providing cutter stock to vacuumline (26) and causing a positive pressure to be applied to the vacuumline (26). After addition of cutter stock to tank (40), typical washingprocedures through nozzle assembly (12) may proceed after which funnel(46) may then be used to suction recirculating product and cutter stockfrom tank (40) to fluid holding tank (66) wherein recirculating productmay be filtered from the sludge (81) and cutter stock and reintroducedinto water supply and pump system (52) in order to redistribute therecirculating product back through the nozzle (39) into the interior ofthe tank (40).

In use, the nozzle assembly (12) and suction pipe (13) of the apparatus(10) are permanently or removably mounted to the vertically extendingsidewall (42) of the storage tank (40) containing adherent sludge (81).The wash pipe (34) and draw pipe (44) extend through the tank sidewall(42) of tank (40) with the exterior portions (34A) of the wash pipe (34)and (44A) of the draw pipe (44) on the exterior (43) of the storage tank(40) and an interior portions (34B) of the wash pipe (34) and (44A) ofthe draw pipe (44) extend into the tank interior (45) of the storagetank (40). The swivel segment (33A) of the submersible swivel joint (33)is then attached to the end (35) of the interior portion (34B) of thewash pipe (34) and the discharge end (37) of the swivel joint (33) isfitted with a choked nozzle (39). The nozzle assembly (12) is thenpositioned adjacent to the floor (45A) of tank (40). The steeringlinkage (28) of the control assembly (14) is then attached to the swiveljoint (33) in a configuration that will allow rotation of the chokednozzle (39) about the centerline of the interior wash pipe (34B) bymeans of the swivel joint (33) when the steering wheel (29) is turned torotate the control shaft (24).

Flow from the choked nozzle (39) is accomplished by attachment ofexterior portion (34A) of the wash pipe (34) to the fluid line (50) atthe tank exterior (43) by means of the attachment flange (38) otherattachment means. The swivel joint (33) with the attached control shaft(24) by means of the associated steering linkage (28) will then allowthe nozzle (39), and any associated flow, to be directed to a desiredposition and location in the interior (45) of the storage tank (40) byrotation and manipulation of the control shaft (24) and associatedsteering linkage (28).

During the process of flow from choked nozzle (39) or after a sufficientflow has been achieved, fluid may be reclaimed through funnel (46) byactivating vacuum system (54) which will draw fluid into funnel (46),through draw pipe (44), and into fluid source (52) where the fluid maythen be recirculated to clean storage tank (40).

FIG. 9 depicts an isometric view of suction section (13) wherein nozzlesection (12) has been omitted to best show the function of the suctionsection (13) being articulable As shown in FIG. 9, suction section (13)may be configured in the same manner as nozzle section (12) shown inFIGS. 3, 4, 5, 6A and 6B. In such a configuration suction section (13)will be provided with ninety degree pipe segments (41 & 48), a steeringlinkage (28A), control rod (27A), and a swivel joint (48) so as to allowfunnel (46) to be positioned adjacent tank floor (45A) and articulatedand positioned as desired, as described for nozzle section (12), toallow suction force to draw in adherent sludge.

It is thought that the proposed apparatus and method for cleaning theinterior of an above ground storage tank presented herein and many ofits attendant advantages will be understood from the foregoingdescription. It is also thought that it will be apparent that variouschanges may be made in the form, construction and arrangement of theparts and steps of the apparatus and method without departing from thespirit and scope of the invention or sacrificing all of its materialadvantages.

We claim:
 1. A method for cleaning the adhered contents of an aboveground storage tank comprising the steps of: (a) providing air aboveground storage tank having a vertically extending sidewall defining atank interior and a tank exterior and a downwardly sloped interior tankfloor; (b) providing a nozzle assembly comprised of a verticallyadjustable nozzle section having a wash pipe with a swivel joint wherebysaid wash pipe may be swiveled and a suction section having a draw pipe;(c) extending wash pipe of said nozzle section of said nozzle assemblythrough said sidewall into said tank interior to a position adjacentsaid tank floor; (d) extending said suction section of said nozzleassembly through said sidewall into said tank interior; (e) providing ahigh pressure fluid supply line and connecting said fluid supply line tosaid nozzle section of said nozzle assembly; (f) providing a suctionassembly on said tank exterior and connecting said suction assembly tosaid suction section of said nozzle assembly; (g ) injecting fluidthrough said nozzle section and washing the adhered contents of saidabove ground storage tank with said injected fluid; (h) providing acontrol mechanism whereby said nozzle assembly may be swiveled from saidtank exterior; (i) swiveling said nozzle assembly about said wash pipeand washing said adhered contents with said injected fluid; and (j)applying vacuum in said suction section and suctioning said adheredcontents and said injected fluid from said above ground storage tank. 2.The method for cleaning the adhered contents of an above ground storagetank as recited in claim 1 comprising the additional steps of: (a)adjusting said nozzle assembly whereby said injected fluid is directedto follow the angle of said downwardly sloped interior tank floor; and(b) washing said adhered contents With said injected fluid through saidadjusted nozzle.
 3. The method for cleaning the adhered contents of anabove ground storage tank as recited in claim 2 comprising theadditional steps of: (a) removing said vacuum in said suction sectionand injecting cutter stock through said suction section into said aboveground storage tank; (b) circulating said cutter stock within said aboveground storage tank by injecting fluid through said nozzle section; (c)applying vacuum in said suction section; (d) suctioning said cutterstock, said adherent contents, and spent said fluid through said suctionsection; (e) filtering said adherent contents from said injected fluidand said cutter stock; and (f) recirculating said injected fluid andsaid cutter stock into said above ground storage tank.
 4. The method forcleaning the adhered contents of an above ground storage tank as recitedin claim 3 comprising the additional steps of: (a) providing a suctionsection comprised of an adjustably extendable draw pipe; and (b)extending said draw pipe to a position adjacent said tank floor.
 5. Themethod for cleaning the adhered contents of an above ground storage tankas recited in claim 4 wherein said wash pipe of said nozzle section iscomprised of multiple pipe segments.
 6. The method for cleaning theadhered contents of an above ground storage tank as recited in claim 5wherein said draw pipe of said suction section is comprised of multiplepipe segments.
 7. A method for cleaning the adhered contents of an aboveground storage tank comprising the steps of: (a) providing an aboveground storage tank having a vertically extending sidewall defining atank interior and a tank exterior and a downwardly sloped interior tankfloor; (b) providing a nozzle assembly comprised of a verticallyadjustable nozzle section having a wash pipe comprised of a plurality ofconnected pipe segments including a connected pipe swivel joint segmentand a suction section having a draw pipe; (c) extending said wash pipeof said nozzle section of said nozzle assembly through said sidewallinto said tank interior to a position adjacent said tank floor; (d)extending said suction section of said nozzle assembly through saidsidewall into said tank interior; (e) providing a high pressure fluidsupply line and connecting said fluid supply line to said nozzle sectionof said nozzle assembly; (f) providing a suction assembly on said tankexterior and connecting said suction assembly to said suction section ofsaid nozzle assembly; (g) injecting fluid through said nozzle sectionand washing the adhered contents of said above ground storage tank withsaid injected fluid; (h) providing a control mechanism whereby saidnozzle assembly may be swiveled about said pipe swivel joint segmentfrom said tank exterior; (i) swiveling said nozzle assembly about saidpipe swivel joint segment and washing said adhered contents with saidinjected fluid; and (j) applying a vacuum through said suction assemblyand suctioning said adhered contents and said injected fluid from saidabove ground storage tank.
 8. The method for cleaning the adheredcontents of an above ground storage tank as recited in claim 7comprising the additional steps of: (a) adjusting said nozzle assemblywhereby said injected fluid is directed to follow the angle of saiddownwardly sloped interior tank floor; and (b) washing said adheredcontents with injected fluid through said adjusted nozzle.
 9. The methodfor cleaning the adhered contents of an above ground storage tank asrecited in claim 8 wherein said wash pipe of said nozzle section iscomprised of multiple pipe segments.
 10. The method for cleaning theadhered contents of an above ground storage tank as recited in claim 9wherein said suction section is comprised of multiple pipe segments. 11.The method for cleaning the adhered contents of an above ground storagetank as recited in claim 10, wherein said step of providing a highpressure fluid supply line and connecting said fluid supply line to saidnozzle section of said nozzle assembly includes the additional steps of:(a) providing a fluid pump in fluid communication with a fluid supply;and (b) connecting said fluid supply to said fluid pump.
 12. The methodfor cleaning the adhered contents of an above ground storage tank asrecited in claim 11, wherein said step of providing a suction assemblyon said tank exterior and connecting said suction assembly to saidsuction section of said nozzle assembly includes the additional stepsof: (a) providing a vacuum pump; (b) providing a vacuum tank andconnecting said vacuum pump to said vacuum tank by vacuum line; (c)providing a fluids collection tank and connecting said fluid collectiontank to said vacuum tank by a vacuum line; and (d) collecting saidadhered contents and said injected fluid in said fluids collection tank.13. The method for cleaning the adhered contents of an above groundstorage tank as recited in claim 12 comprising the additional steps of:(a) removing said vacuum from said suction pipe and injecting cutterstock through said suction section into said above ground storage tank;(b) circulating said cutter stock within said above ground storage tankby injecting fluid through said nozzle section; (c) applying vacuumthrough said suction section by said vacuum pump; (d) suctioning saidcutter stock, said adherent contents, and said injected fluid throughsaid suction section; (e) filtering said adherent contents from saidinjected fluid and said cutter stock; and (f) recirculating of saidinjected fluid and said cutter stock into said above ground storagetank.
 14. The method for cleaning the adhered contents of an aboveground storage tank as recited in claim 13 comprising the additionalsteps of: (a) providing a Suction section comprised of an adjustablyextendable draw pipe; and (b) extending said draw pipe to a positionadjacent said tank floor.